Stopping device for electric hoists.



entre HERBERT s.

yannurmn, or manine, PENNSYLVANIA, Asssnon To BEADNG CRANE t HOIST WQRKS, OF READING, PENNSYLVANI.

STOPPING DEVICE EOE ELECTRIC HOISTS.

LBSS,

Specification o Letters Fatent.

patented Apr. 29, 1913.

pplcation .led July 24:, 1912. Y Serial No. 711,371.

To all wiiomz'z may concern:

Be it known that l, HERBERT S. VALEN- 'rrmn citizen ot the United States, residing at Reading, in the count-y ot Berks and State of Pennsylvania, have invented certain new and useful improvements 'in Stopping llevices for Electric Hoists, oi' Which the tollowing is a specification.

My invention particularly relates to autoand is especially applicable to electric lidists, tor limiting thel rotation of the drums and the consequent throw ot the load lit'ting hook.

lllhe principal objects of my invention are to provide simple and eiticient means to au= tomaticaliy stop the motor ot an elect-ric hoist when theelitting hook has reached the predetermined limit ot its throw in either its raising or lowering movement; and to provide means adjustable to vary the limit of movement ot said hook in either direction independently.

@ther objects of my invention,specifically stated, are to provide manually actuated mechanism tor controlling .the winding drum, with means to normally maintain it in an inoperative position, and to connect automatically actuated mechanism therewith, having means actuated by the rotation ot said drum to @Elect the actuation ot said controlling mechanisms tor stopping said winding drum when it has made a predetermined numifer ot revolutions.

This invention also includes all ot the various novel tentures ot construction and arrangement or the parts as hereinafter more detinitely specified. f

ln the. accompanying drawings, Figure l is a fragmentary end elevation ot an electric hoist conveniently embodying stopping mechanism constructed in accordance with my invention, and Fig. 2 is a fragmentary sectional elevation ot said hoist as seen from the right hand of Fig. l.

ln said figures the gear casing 3 provides suitable bearings 4- and 5 for the shat't G, which is driven by the gear T, and which carries the Winding drums 8 and 9, around which the oppositeends ot the hoisting cable l0 are helically coiled.

rThe rotation ot the drums 8 and 9 is conm :iiently controlled by controlling mechanism included in the controller casing i9 7 projecting incre actuated sheave le pinned thereto, and having the cords 15 and 16 secured thereto and respectively depending peripherally from the diametrically opposite cylindrical surfaces ot said sheave through the eyes 18 and lil in theguide Q0, and having the hand grips Q1 and Q2 respectiigely, by which it lma7 be. partially rotated in either direction.

rlhe sheave 14 and the shaft 13 are normally maintained in a neutral or inoperative position by the spring Q4 which is coiled around the hub ofthe sheave 14 and has its opposite tree ends extending therefrom in substantially parallel relation on respectivelyT opposite sides of the stationary pin projecting from the casing 1&2- and the movable pinl projecting from the sheave ll in substantially parallel relation with the pin 2o and movable with respect thereto in a cylindrical path in opposition to tension ot said spring which tends to shit't said pins 25 and 2T into a common plane with the axis of the shaft 13, and

thereby maintain the controlling mechanism inoperative.

rlhe guide QG is loosely mounted on the shaft 13, between the manually actuated sheave 14 and the automatically actuated sheave 30, which also pinned on the shatt 123 and which connected by the crossed belt 31 to rotate with the sheave B2, having the miter gear 33 loosely journaled on the stud projecting from the bracket which is carried by the drum 8, said stud Sel being coaxial with the shaft (l upon which said drum is mounted.

rlhe bracket 35 is provided rwith the bosses 3S and S9 respectively having the shoulders l0 and all forming convenient stops, and having coaxially alincd apertures through which the screw threaded stopping shaft 42 extends in threaded engagement with the boss 38.

The screw shaft 4Q .is provided at its op- -forming stops respectitfely ar ringed to engage the stops 40 and il on the bosses 38 and 39 to limit the rotation and consequent axial vmovement ot the screw shaft 4t2.

The rotation oi the screw sl itt 42 is convenient-ly eiiected by the miter gear 55 which is mounted thereon between the bosses 38 les 'such rotation of the drum 8 carries the miter gear 55in a cylindrical path about theY axis of rotation of said druin, in toothed engage ment With the miter gear 33, which being held stationary causes the gear 55 to rotate the 'screw shaft 42 until the stop on said shaft engages its cooperative stop on the boss, Which prevents further relative rotation of thev screw shaft 42, thereby locking the gears in relatively fixed relaton,`so that the further rotation ofthe Winding drums effects a similar rotationof the gear 33, and the controlling' mechanism connected there- With, to return the shaftl 13 toits neutral or inoperative position shown in the drawings.

It is not desired to limit this invention to the precise detailsof construction and arrangement herein set forth, as it is obvious that various modifications may be made therein Withoutdeparting froni'the essential features of the invention as defined in the appended claims.

Having thus described my invention, l claim :-q

l. ln an electric hoist, the combination with driving shaft, of a controller therefor, having a shaft, a sheave secured .on said shaft, means for rotating said sheave and shaft, means for limiting the rotation of said sheave and shaft, and tending to return theinto inoperative position, a secondv lsheave secured tosaid shaft, a sheave earried by said driving shaft in coaxial, relatively rotatable relation therewith, a belt connecting the second mentioned sheave with the third, a miter gear in fixed relation with the sheave on said driving shaft, a threaded shaft carried by said driving shaft, a miter gear con- 'l *A nected to rotate said threaded shaft, andcarried by said driving shaft in a cylindricalpath in toothed engagement with the first mentioned gear, and means actuated by the rotation of said threaded shaft to stop its rotation,fand lock said gears in relatively fixed relation. 1

2.v ln stopping mechanism having controlling lmechanism, the combination with a bracket having shoulders forming stops, and a stud shaft, of a miter gear -n'iounted for rotation on said shaft, means operatively connecting said gear with said controlling" mechanism, a screw shaft in threaded engagement With said bracket and rotatable on an axis transverse to the axis of rotation of screw shaft, and carried in a cylindrical pat-h in toothed engagement with the rst mentioned gear, and means carried by said screw shaft for engaging said stops and preventing further rotation of said shaft and gear on the transverse axis, to lock` said gears in relatively fixed relation.

ln testimony whereof l afrix my'signature in presence of two Witnesses;

HERBERT S, VALENTNE.

1Wit -esses:

En. A. KELLY, ARYE. SrAUrr-na said studshaft, a miter gear keyed to said A 

